What’s in a light?

The maintenance-required light should be thought of as a final step to any service, just like the last fluid-level check prior to closing the hood. When your customers leave the shop, they have the expectation that something was done to their cars. If the indicator comes on shortly after leaving, it casts doubt on what was actually accomplished. Sure, some customers are understanding when you explain that it was a simple oversight and they can return to the shop to have it cleared for free. But what about the customers who won’t call, and likewise, won’t ever return?
Many maintenance indicators are simple odometer counters calibrated to turn on after a certain number of miles since last it was turned off. This can be somewhat of a paradox when your shop’s oil change recommendation is 3,500 miles, but Toyota’s maintenance indicator turns on at 4,500. Should you try to convince your customers that the Toyota-programmed light is incorrect? Consider explaining to your customers that the light functions more like the “low-fuel” light, where it’s the longest you possibly can go without service before risking problems from neglect. If you’re in the habit of clearing the light properly at your shop’s 3,500 mile interval, your regular customers should never see the indicator.
Many customers have a misconception about the roles of the MIL and the maintenance required light. Certainly, you’ve heard a customer calling to make an appointment because the car “just needs a tune up and oil change, or something,” because the MIL is on. It takes time to explain to customers that the check engine light is a malfunction indicator, not something routine maintenance will correct. On the other hand, the maintenance required light can inadvertently stress out a customer who was recently in for service -- “But now there’s a light that says maintenance required! Why?!”
We all know how much of a pain it can be to look up the reset procedure for the indicator, especially since it’s often different from vehicle to vehicle. Luckily, an online resource like ALLDATA should have the majority of procedures a few clicks away. Choose the vehicle, click the “Maintenance” subsection at the left, and you should see a link on the right for “Maintenance Indicator Reset.” But what about the tricky luxury cars with on-screen displays like Nissan or Infiniti? What about “intelligent,” logic-driven reminder systems that can only be reset with a scan tool? We’ll cover those more in detail later, but you should always strive to turn the indicator off!

Basic reminder systems

[caption id="" align="alignright" width="288"] Use special service tool #00012 to reset the maintenance indicator on this 1992 Honda Accord.[/caption]
Unfortunately, the days are gone when you could stick the key into the gauge cluster to reset the reminder from red back to green. But f you become familiar with your shop’s most commonly seen vehicles, resetting the maintenance-required indicator can become nearly as easy. In addition to being simple to reset, these basic reminder systems are controlled by mileage alone.
Most manufacturers do not allow the vehicle owner to customize the reminder interval, and they only publish how the light will perform in the owner’s manual. A modern Honda Civic from 2001-2005, for example, will go for 8,000 miles before the light stays on! In fact, it doesn’t stay lit all the time. After the key-on bulb check, the light will remain for an additional two seconds. It isn’t until after 10,000 miles that the light actually remains on as a constant reminder. You can imagine the